Coiled pipe dispensing rack

Information

  • Patent Grant
  • 6260790
  • Patent Number
    6,260,790
  • Date Filed
    Friday, December 24, 1999
    24 years ago
  • Date Issued
    Tuesday, July 17, 2001
    22 years ago
  • Inventors
  • Examiners
    • Marcelo; Emmanuel M.
    Agents
    • Kremblas, Foster, Phillips & Pollick
Abstract
A coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, with the rack comprising a main cage, a hub and spindle assembly, and a mounting unit. The main cage comprises a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe therebetween. Both the first and second portion each comprise a center plate, a plurality of strut arms, and an exterior side wall, with each of the strut arms connected to and radiating outwardly from the respective center plate, and with each of the strut arms connected to the respective exterior side wall. The hub and spindle assembly is positioned intermediate the main cage and the mounting unit. The mounting unit remains in contact with the moving vehicle as the pipe is unrolled.
Description




FIELD OF THE INVENTION




The present invention relates generally to pipe, and more particularly, to a device which is used to dispense plastic pipe from a coil. Although many types of pipe could be dispensed using the device of this invention, the device has special application for use with the type of pipe used in natural gas lines or pipelines.




BACKGROUND OF THE INVENTION




This invention is directed to the providing of a device for use in the laying of pipe, and more particularly for use in the laying of pipe of the type used in natural gas lines or pipelines, although it is recognized that the use of the device of this invention may also have application in the laying of other types of pipe, such as drainage pipe. When it came to the laying of plastic pipe for gas pipelines, originally this was done by manually unrolling the flexible plastic pipe from large coils. In order to grasp a better understanding of the magnitude of the task, it should be appreciated that a 500′ long roll of pipe weighs about 350 pounds. Therefore, in actual practice four or five individuals were needed in order to control the coiled pipe as it was unrolled. This strenuous job was also very time consuming. For example, it might take 4½-5 hours to unroll a 500′ long roll of pipe. Additionally, the coiled pipe was kept coiled and compact through the use of a plurality of retaining bands which when periodically cut, so as to effectuate the further unrolling of the pipe (typically 25′ at a time between retaining bands), sometimes resulted in the pipe springing out uncontrollably, thereby injuring one or more of the workers standing nearby.




More recently, alternatives were developed for the dispensing of coiled plastic pipe. One such device is disclosed in U.S. Pat. No. 4,949,909 to Hatfield. The pipe coil dispensing rack disclosed in that patent provided a turntable atop a frame, such that the pipe could be unwound from the stationary device in cooperation with a moving pipe puller. One significant drawback associated with such a device is its stationary nature. In order to lay pipe using that embodiment of a dispensing rack, the pipe must be unrolled using a pipe puller, cut at or near the rack once the predetermined amount of pipe has been laid, and then a worker must return to and move such a rack to a new location where the installation process is repeated or else a worker must always remain with the rack. Although easier than the original procedure, this method still is fairly time consuming due to having a worker return over and over again to the dispensing rack in order to move it to its next location or else dedicating a worker to staying with the rack the entire time the pipe puller is in operation.




In the natural gas pipeline industry, the problem has been addressed by utilization of a pipe-coil trailer, which specially built unit is pulled by a truck. The trailer orients the coiled pipe horizontally and permits it to be unwound from the trailer as the trailer is pulled over the ground. However, these trailers typically still require 3 people to lift the heavy coil of pipe up into its horizontal position atop the trailer. Additionally, the terrain often limits the use and effectiveness of this alternative. Moreover, since it is common to have a two ton utility truck pull the pipe-coil trailer, this approach requires that a utility truck be dedicated for the pulling operation. Oftentimes, this is not possible due to the scheduling of the trucks, consequently resulting in the delay of the installation of the gas pipe.




It is thus apparent that the need exists for an improved pipe dispensing device for use with the type of coiled plastic pipe which is utilized in the gas pipeline industry.




SUMMARY OF THE INVENTION




In accordance with this invention there is disclosed a coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe. The rack comprises a main cage, a hub and spindle assembly, and a mounting unit. The main cage comprises a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe, while the mounting unit is in contact with the moving vehicle as the pipe is unrolled. The hub and spindle assembly is positioned intermediate the main cage and the mounting unit.




The main cage first portion comprises a center plate, a plurality of strut arms, and an exterior side wall, with each of the strut arms connected to and radiating outwardly from the center plate, and with each of the strut arms connected to the first portion's exterior side wall. There also are a plurality of coil supports, with each coil support being secured to a strut arm. The main cage first portion also includes a plurality of gussets, with each of the gussets being secured to a coil support and also to the center plate. At least one mounting pin is secured to the main cage first portion. The main cage second portion comprises a center plate, a plurality of strut arms, at least one locking plate, and an exterior side wall, with each of the strut arms connected to and radiating outwardly from the center plate, and with each of the strut arms connected to the main cage second portion's exterior side wall. Each aforementioned mounting pin is secured to the main cage first portion, as well as cooperating with a respective locking plate to retain a coil of plastic pipe between the first and second portions of the main cage.




The hub and spindle assembly includes a hub portion and a spindle portion, with the hub portion having a front wall which is in contact with the center plate. The spindle portion includes a connecting tube and a retaining plate, with the connecting tube engaging the mounting unit. The retaining plate cooperates with the mounting unit to secure the hub and spindle assembly to the mounting unit.




The mounting unit includes a pair of opposing side walls separated by a plurality of spacing bars. The mounting unit also has a connecting channel which engages the hub and spindle assembly. Additionally, the mounting unit has at least one retaining plate cooperating with the hub and spindle assembly to secure the mounting unit to the hub and spindle assembly.




There is also disclosed a coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, with the rack comprising a main cage, a hub and spindle assembly, and a mounting unit. The main cage comprises a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe. The main cage first portion comprises a center plate, a plurality of strut arms, a plurality of coil supports, with each coil support being secured to a strut arm, a plurality of gussets, with each of the gussets being secured to a coil support and also to the center plate, at least one mounting pin secured to the main cage first portion, and an exterior side wall. Each of the strut arms are connected to and radiate outwardly from the center plate, and each of the strut arms are connected to the exterior side wall. The main cage second portion comprises a center plate, a plurality of strut arms, at least one locking plate, and an exterior side wall, with each of the strut arms connected to and radiating outwardly from the center plate, and with each of the strut arms connected to exterior side wall. Each mounting pin cooperates with a respective locking plate to retain a coil of plastic pipe between the first and second portions. The mounting unit is in contact with the moving vehicle as the pipe is unrolled, with the hub and spindle assembly positioned intermediate the main cage and the mounting unit.




The hub and spindle assembly includes a hub portion and a spindle portion, with the hub portion having a front wall, with that front wall being in contact with the center plate. The spindle portion comprises a connecting tube and a retaining plate, with the connecting tube engaging the mounting unit. The retaining plate cooperates with the mounting unit to secure the hub and spindle assembly to the mounting unit.




The mounting unit comprises a pair of opposing side walls separated by a plurality of spacing bars, a connecting channel to engage the hub and spindle assembly, and at least one retaining plate cooperating with the hub and spindle assembly to secure the mounting unit to hub and spindle assembly.




There is also disclosed a coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, with the rack comprising a main cage, a hub and spindle assembly, and a mounting unit. The main cage comprises a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe. The main cage first portion comprises a center plate, a plurality of strut arms, a plurality of coil supports, with each coil support being secured to a strut arm, a plurality of gussets, with each of the gussets being secured to a coil support and also to the center plate, at least one mounting pin secured to the main cage first portion, and an exterior side wall, with each of said strut arms connected to and radiating outwardly from the center plate, and with each of the arms connected to the exterior side wall. The main cage second portion comprises a center plate, a plurality of strut arms, at least one locking plate, and an exterior side wall, with each of the strut arms connected to and radiating outwardly from the center plate. Each of the strut arms are connected to the exterior side wall, and each mounting pin cooperates with a respective locking plate to retain a coil of plastic pipe between the first and second portions, such that the mounting unit in contact with the moving vehicle as the pipe is unrolled. The hub and spindle assembly is positioned intermediate the main cage and the mounting unit, with the hub and spindle assembly comprising a hub portion and a spindle portion. The hub portion has a front wall, which front wall is in contact with the center plate. The spindle portion comprises a connecting tube and a retaining plate, with the connecting tube engaging the mounting unit. The retaining plate cooperates with the mounting unit to secure the hub and spindle assembly to the mounting unit. The mounting unit comprises a pair of opposing side walls separated by a plurality of spacing bars, a connecting channel for engaging the hub and spindle assembly, and at least one retaining plate cooperating with the hub and spindle assembly to secure the mounting unit to the hub and spindle assembly.




The primary objective of this invention is to provide a device for the dispensing of plastic pipe from a coil, which device is of relatively economical construction and is particularly easy to utilize in the laying of pipe.




Another objective of this invention is to provide a device for the dispensing of plastic pipe from a coil, which dispensing operation can take place using at most 3, and preferably only 2, workers.




Still another objective of this invention is to provide a device for the dispensing of plastic pipe from a coil, such that the pipe can be laid relatively quickly.




Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings, and the appended claims.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a side elevational view of a coiled pipe dispensing rack made in accordance with the present invention being used in conjunction with a back-hoe.





FIG. 2

is an exploded perspective view of the coiled pipe dispensing rack of this invention.





FIG. 3

is an side elevational view of the main cage portion of the invention, when the main cage is laying on the ground.





FIG. 4

is a top plan view of FIG.


3


.





FIG. 5

is a perspective view of the hub assembly of the invention taken from the rear of FIG.


1


.





FIG. 6

is a side elevational view of the mounting unit component of the invention taken from the left side of FIG.


1


.





FIG. 7

is a side elevational view of the mounting unit component of the invention taken from the right side of FIG.


1


.





FIG. 8

is a front elevational view of the mounting unit component of the invention taken from the front of FIG.


1


.











DETAILED DESCRIPTION OF THE DRAWINGS




Having reference to the drawings, attention is directed first to

FIG. 1

which discloses a coiled pipe dispensing rack made in accordance with the invention designated generally by the numeral


10


. In actual use the rack is utilized along with a vehicle V to quickly and easily unroll pipe P. As will be discussed below, although the vehicle V could be a truck or tractor, excellent results have been obtained with the vehicle being a back-hoe.




As mentioned above, the coiled pipe P used in natural gas pipelines features retaining bands R which wrap the coiled pipe such that only 25′ or so at a time can be dispensed from the rack. Although one of the problems associated with the cutting of these bands has been the tendency of the pipe to uncoil uncontrollably, it will be appreciated that the coil is “encased” within the rack so as to limit the extent to which it can uncoil.




Turning now to a discussion of the components which make up this invention, attention is directed first to a comparison of

FIGS. 2

,


3


, and


4


. Generally, the pipe dispensing rack of the invention is comprised of a main cage


12


, a hub and spindle assembly


14


, and a mounting unit


16


. The main cage is approximately 7′ across and is comprised of a first portion


20


and a second portion


25


as can best be appreciated from FIG.


2


.




A more careful consideration of the first portion


20


discloses that it is features a center plate


30


. This center plate


30


has a top surface


31


and a bottom surface


32


. Further, the center plate


30


has a distinctive looking center aperture


34


characterized by a plurality of slots or indentions at the periphery of the center aperture which extend outwardly into the center plate. The center plate


30


also has an outer peripheral edge


36


. Structurally, the center plate is formed of {fraction (1/4+L )}″ thick flat steel that is 28″ in diameter.




Returning now to a comparison of

FIGS. 2

,


3


, and


4


, the first portion


20


of the main cage


12


also features a plurality of strut arms


40


. As shown there are six such strut arms


40


, each having a first or proximal end


42


and a second or distal end


44


. The proximal end


42


is adjacent to the center plate


30


to which it is welded. Meanwhile, the distal end of each strut arm


40


is welded to edge plates


46


. Each edge plate


46


has a first end


47


and a second end


48


. Each edge plate has its first end


47


secured to the directly adjacent edge plate's second end


48


. It is at the juncture of the adjacent edge plates that each strut arm is also attached as can best be appreciated from

FIGS. 2 and 4

. Each strut arm


40


is formed from T-iron, such that there is an upright portion


50


and crossbar portion


52


.




Another feature of the first portion


20


is the inner spool supports or coil supports


54


also formed of T-iron such that each coil support


54


has an upright portion


55


and a crossbar portion


56


. In the preferred embodiment of the invention, the base of each coil support


54


is secured to the crossbar portion


52


of the corresponding strut arm


40


, preferably perpendicular thereto. At the top of each coil support, a {fraction (1/4+L )}″ thick and {fraction (3/4+L )}″ wide gusset


57


is attached to the upright portion


50


and angled downwardly towards the center plate


30


where its opposite end is secured.




Still another feature of the first portion of the main cage is the at least one mounting pin


58


which is used to effectuate the securing of the first and second portions of the main cage together. In the preferred embodiment of the invention there are three such mounting pins. Each pin


58


is formed of a cylindrical rod secured to the center plate


30


so as to preferably be perpendicular thereto. Near the top of each pin is a mounting pin aperture which extends through each pin


58


. Adjacent each pin is a support plate


59


having a lip


61


along its top edge as can best be seen in FIG.


3


. As can be appreciated from a comparison of

FIGS. 1 and 2

, the second portion of the main cage rests upon the lip


61


. The support plate is formed of a sheet of metal with the length of its base being greater than the length of the lip


61


. The base of the support plate is secured to the center plate, with each mounting pin/support plate combination shown as preferably being closer to the center aperture


34


than the coil supports.




With respect to the second portion


25


of the main cage


12


, it will be appreciated that it too has a center plate. Second portion center plate


65


has a top surface


66


and a bottom surface


67


. Additionally, as can be appreciated from

FIGS. 1 and 2

, a short length of pipe projects from the center plate so as to form a wire spool holder


68


.




The second portion


25


also has second portion strut arms


70


. As shown there are six such strut arms


70


, each having a first or proximal end


72


and a second or distal end


74


. The proximal end


72


is adjacent to the center plate


65


to which it is welded. Meanwhile, the distal end of each strut arm


70


is welded to edge plates


76


. Each second portion edge plate


76


has a first end


77


and a second end


78


. Each edge plate has its first end


77


secured to the directly adjacent edge plate's second end


78


. It is at the juncture of the adjacent edge plates that each strut arm is also attached as can best be appreciated from FIG.


2


. Each strut arm


70


is formed from T-iron, such that there is an upright portion


80


and crossbar portion


82


.




Spanning at least one pair of adjacent strut arms


70


, and preferably at least three pairs as shown, are locking plates or brackets


90


made from {fraction (1/4+L )}″ steel plate secured at its opposing ends to adjacent strut arms. Near the center of each locking plate


90


is an aperture


92


. Suitable retaining means


94


, such as clips or other fastening means, are secured by connecting means


93


to each locking plate. The connecting means


93


could take the form of a chain. The mounting pin


58


is inserted through the hole in the bracket


90


, and retaining means


94


is preferably inserted through the mounting pin aperture


60


to fasten the second and first portions together. It will be appreciated that strut arms


40


are in a first plane associated with the main cage first portion, and strut arms


70


are in a second plane associated with the main cage second portion, with the distance between these planes being about 15″. These planes are parallel to each other and spaced apart with the coiled pipe being intermediate the planes.




Turning now to a comparison of

FIGS. 2 and 5

, the hub and spindle assembly


14


is shown as including a hub portion


95


and a spindle portion


105


. In reality, these two components function much like a hub and an axle. The hub portion


95


has a front wall


96


having a plurality of front wall apertures


98


. Bolts


99


secure the hub portion to the center plate


30


. The hub portion


95


also has a rear wall


100


to which is attached a brake mechanism


102


of the type well known in the art associated with hubs and axles. In actual use, this brake mechanism


102


can be actuated if the pipe is uncoiling too fast, and as such can be used to control the rate of dispensing.




The spindle portion


105


has a first end


106


and a second end


108


. A connecting tube


110


is secured to the hub portion


95


at the first end of the spindle portion. Atop the connecting tube


110


is a retaining plate


112


. This small plate has an aperture


114


formed therethrough. A connecting means, such as a chain, is used to keep suitable retaining means


115


handy. The spindle retaining means


115


could take the form of clips or other fastening means, and are secured by connecting means


113


to the hub and spindle assembly.




Turning now to a comparison of

FIGS. 2

,


6


,


7


, and


8


, it will be appreciated that the mounting unit


16


is formed having two pairs of mounting unit retaining plates


118


, with each of the plates having apertures


119


. The reason for having two pairs of mounting unit retaining plates is so that the pipe can be dispensed from either side of the vehicle, in particular a back-hoe. The apertures in the mounting unit retaining plates


118


can be aligned with the apertures in the spindle retaining plate. When so aligned, the retaining means


115


can be inserted through the apertures to effectuate the fastening of the hub and spindle assembly to the mounting unit.




The mounting unit


16


also has a pair of side walls


120


having a planar top edge


121


and a curved bottom edge


122


. The shape of the side walls is particularly important when a back-hoe is chosen as the vehicle to carry the pipe dispenser during the installation process. The curved shape of the side walls


120


enables the back-hoe to be maneuvered into a “closed” position whereby the mounting unit is held securely within the back-hoe bucket.




The mounting unit's side walls


120


also feature an elevated portion


123


having an aperture


124


. The side walls themselves are separated by the presence of a plurality of spacing bars


125


,


126


, and


127


. Extending between each of the elevated portions


123


is connecting channel


130


which in actual use has the connecting tube


110


inserted therein. The connecting channel is formed from 1¼″ diameter pipe, while each of the side walls of the mounting unit is formed from {fraction (3/8+L )}″ thick steel plate.




In actual use, the device is formed by placing the mounting unit in a vehicle, such as the bucket of a back-hoe. The hub and spindle assembly can then be secured to the mounting unit. Then the first portion is bolted to the hub portion. The pipe to be installed is then laid onto the strut arms of the first portion such that the inside of the coil is adjacent the coil supports


54


. The second portion is then aligned adjacent the first portion such that at least one mounting pin


58


can be secured to locking plate


90


.




In actual pipe installation, the coiled pipe dispensing rack of this invention can unroll hundreds of feet of pipe in a fraction of the time previously needed to accomplish the job manually. Moreover, this can be accomplished using fewer workers and at a lower risk of injury. As the pipe is unrolled, a coil of wire which has been placed over the wire spool holder permits a wire to be unrolled contemporaneously with the pipe, since in practice a metallic substance is laid in the trench with the pipe to permit the location of the plastic pipe to be detected from above ground in case service is needed, and the presence of the wire facilitates the use of a conventional metal detector.




Therefore, not only is the coiled pipe dispensing rack of this invention relatively easy to fabricate, but it is also very easy to utilize. Consequently, the invention results in a considerable reduction in labor as well as time and installation expense.




While the form of apparatus herein described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form of apparatus and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.



Claims
  • 1. A coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, said rack comprising a main cage, a hub and spindle assembly, and a mounting unit, said main cage comprising a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe, said main cage first portion comprising a center plate, a plurality of strut arms, and an exterior side wall, each of said strut arms connected to and radiating outwardly from said center plate, each of said strut arms connected to said exterior side wall, said mounting unit in contact with the moving vehicle as the pipe is unrolled, said hub and spindle assembly positioned intermediate said main cage and said mounting unit.
  • 2. The device according to claim 1 which includes a plurality of coil supports, each coil support being secured to a strut arm.
  • 3. The device according to claim 2 which includes a plurality of gussets, each of said gussets being secured to a coil support and also to said center plate.
  • 4. The device according to claim 1 which includes at least one mounting pin secured to said main cage first portion.
  • 5. The device according to claim 1 wherein said main cage second portion comprises a center plate, a plurality of strut arms, at least one locking plate, and an exterior side wall, each of said strut arms connected to and radiating outwardly from said center plate, each of said strut arms connected to said exterior side wall.
  • 6. The device according to claim 5 which includes at least one mounting pin secured to said main cage first portion, each said mounting pin cooperating with a respective locking plate to retain a coil of plastic pipe between said first and second portions.
  • 7. The device according to claim 1 wherein said hub and spindle assembly comprises a hub portion and a spindle portion, said hub portion having a front wall, said front wall being in contact with said center plate, said spindle portion comprising a connecting tube and a retaining plate, said connecting tube engaging said mounting unit, said retaining plate cooperating with said mounting unit to secure said hub and spindle assembly to said mounting unit.
  • 8. The device according to claim 1 wherein said mounting unit comprises a pair of opposing side walls separated by a plurality of spacing bars, a connecting channel to engage said hub and spindle assembly, and at least one retaining plate cooperating with said hub and spindle assembly to secure said mounting unit to said hub and spindle assembly.
  • 9. The device according to claim 1 wherein said main cage first portion comprises a plurality of strut arms having associated therewith a first plane, and wherein said main cage second portion comprises a plurality of strut arms having associated therewith a second plane, said planes being parallel to each other and spaced apart with coiled pipe being intermediate said planes.
  • 10. A coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, said rack comprising a main cage, a hub and spindle assembly, and a mounting unit, said main cage comprising a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe, said main cage second portion comprising a center plate, a plurality of strut arms, at least one locking plate, and an exterior side wall, each of said strut arms connected to and radiating outwardly from said center plate, each of said strut arms connected to said exterior side wall, said mounting unit in contact with the moving vehicle as the pipe is unrolled, said hub and spindle assembly positioned intermediate said main cage and said mounting unit.
  • 11. The device according to claim 10 which includes at least one mounting pin secured to said main cage first portion, each said mounting pin cooperating with a respective locking plate to retain a coil of plastic pipe between said first and second portions.
  • 12. The device according to claim 10 wherein said mounting unit comprises a pair of opposing side walls separated by a plurality of spacing bars, a connecting channel to engage said hub and spindle assembly, and at least one retaining plate cooperating with said hub and spindle assembly to secure said mounting unit to said hub and spindle assembly.
  • 13. The device according to claim 10 wherein said main cage first portion comprises a plurality of strut arms having associated therewith a first plane, and said main cage second portion comprises a plurality of strut arms having associated therewith a second plane, said planes being parallel to each other and spaced apart with coiled pipe being intermediate said planes.
  • 14. A coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, said rack comprising a main cage, a hub and spindle assembly, and a mounting unit, said main cage comprising a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe, said mounting unit comprising a pair of opposing side walls separated by a plurality of spacing bars, a connecting channel to engage said hub and spindle assembly, and at least one retaining plate cooperating with said hub and spindle assembly to secure said mounting unit to said hub and spindle assembly, said mounting unit in contact with the moving vehicle as the pipe is unrolled, said hub and spindle assembly positioned intermediate said main cage and said mounting unit.
  • 15. A coiled pipe dispensing rack for use in cooperation with a moving vehicle to effectuate the unrolling of plastic pipe, said rack comprising a main cage, a hub and spindle assembly, and a mounting unit, said main cage comprising a first portion and a second portion which cooperate with each other to retain a coil of plastic pipe, said main cage first portion comprising a plurality of strut arms having associated therewith a first plane, said main cage second portion comprising a plurality of strut arms having associated therewith a second plane, said planes being parallel to each other and spaced apart with coiled pipe being intermediate said planes, said mounting unit in contact with the moving vehicle as the pipe is unrolled, said hub and spindle assembly positioned intermediate said main cage and said mounting unit.
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Number Date Country
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